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Tropical Storm Arthur

I have been asked a couple questions in regard to Tropical Storm Arthur.

1) Why did the NHC start advisories on a weak tropical storm that was already centered on the coast of Belize and moving inland? The answer to this question is easy. The system met all the qualifications of a tropical cyclone, and there were ship and buoy reports of winds to tropical storm force. The NHC would have been negligent if it had not designated the system a tropical storm and issued advisories.

2) Why was the system given the name Arthur in the Caribbean when it obviously formed from the remnants of Eastern Pacific Tropical Storm Alma? The answer to this questions comes from the National Weather Service Directive on Tropical Cyclone Products. The Directive states “The following rules apply for tropical cyclones passing from one basin to another. Retain the name if a tropical cyclone passes from one basin into another basin as a tropical cyclone, i.e., advisories are continuous….If the remnants of a tropical cyclone regenerate in a new basin, the regenerated tropical cyclone will be given a new designation.” The surface circulation associated with Tropical Storm Alma dissipated over the mountains of Central America by Friday morning. The clouds and mid-level circulation associated with Alma continued moving into the Northwest Caribbean, but a new surface circulation didn’t become apparent until Saturday. Given that the advisories were not continuous due to the inability to identify a surface circulation, National Weather Service rules state that the regenerated tropical cyclone be given a new designation in the new basin (Caribbean).